Pesticide for the protection of wood comprising a mixture of methyl 2-benzimidazole-carbonate or a salt thereof and the aluminum salt of N-nitroso-N-cyclohexylhydroxylamine

ABSTRACT

New and valuable pesticides containing a mixture of active ingredients and a method of combatting pests with the said mixture.

United State Pommer et a1.

[73] Assignee: BASF Aktiengesellschaft,

Ludwigshafen (Rhine), Germany [22] Filed: Oct. 12, 1973 [21] Appl. No.: 405,807

[52] U.S. C1. 424/273; 117/147; 260/22; 424/325 [51] Int. Cl. A01n 9/20; AOln 9/22 1 1 Sept. 2, 1975 [58] Field of Search 424/273, 325

[56] References Cited UNITED STATES PATENTS 3,639,630 2/19'72 Sander et a1 424/325 FOREIGN PATENTS OR APPLICATIONS 1,195,180 6/1970 United Kingdom 815,538 6/1959 United Kingdom PrimaryExaminerJerome D. Goldberg Assistant Examiner-Allen J. Robinson Attorney, Agent, or Firm.lohnston, Keil, Thompson & Shurtleff [5 7] ABSTRACT New and valuable pesticides containing a mixture of active ingredients and a method of combatting pests with the said mixture.

3 Claims, N0 Drawings PESTICIDE FOR THE PROTECTTON OF WOOD COMPRISING A MIXTURE ()F METHYL Z-BENZIMIDAZOLE-CARBONATE OR A SALT THEREOF AND THE ALUMINUM SALT ()F N-NITROSO-N-CYCLOHEXYLHYDROXYLAMINE The present invention relates to a new and valuable pesticide containing a mixture of active ingredients and a method of combatting pests with the said mixture.

It is known that salts of N-nitroso-N-cyclohcxylhydroxylaminc (NCH) may be used for the protection of wood against attack by fungi such as Cmziup/mrn (erhella, Meruliux lac'rimans, Lenlinux lvpidux, etc. Of the salts of NCH which are practically insoluble in water the aluminum salt has proved to be suitable; it is a disadvantage however that fairly high concentrations have to be used to protect the wood. It is also disadvantageous that this compound is not effective (when used in concentrations adequate for combatting ligniperdous fungi) against wood-discoloring fungi such as Pul- Iuluria pullulmzs and Sclemplwmu pityuphilu.

It is also known that methyl 2- benzimidazolccarbamatc (BCM) can be used for combatting a multitude of fungi which belong mainly to the Ascomycetcs and Fungi imperfecti classes; employed in the usual concentrations this compound is ineffective against ligniperdous fungi of the Basidiomycctes class.

We have now found that a mixture of BCM, or an alkali metal salt thereof, and the aluminum salt of NCH is suitable as a pesticide.

Examples of suitable alkali metal salts are the sodium and potassium salt. The sodium salt is preferred.

The pests concerned are fungi and insects in general and particularly those fungi and insects which damage wood, wood coatings or paints.

Pesticides according to the invention advantageously contain as solvent a glycol ether derivative because the active ingredients and particularly the sodium salt of BCM have good solubility therein. Examples of glycol ether derivatives are methyl glycol. n-butyl glycol, methyl diglycol, ethyl diglycol. dipropylene glycol, butyldiglycol, and polyhydric alcohols such as monoethylene glycol, diethylene glycol, triethylene glycol and propylene glycol. Dipropylene glycol is preferred.

Pesticides according to the invention have a fungicidal effectiveness which is more than the sum of the effectiveness of the individual active ingredients, i.e., synergism is evident. The ratio in which the active ingredients are mixed may be varied within a wide range. For example an outstanding action on pests is achieved at a weight ratio of aluminum salt of NCH to BCM or an alkali metal salt of BCM of from l:l to :1, preferably 2:1 to 4:1.

A liquid oily wood preservative which is applied at the rate of from 100 to 200 ccm/m of wood surface may contain up to 4% (by weight) of aluminum salt of NCH and up to 171 of the sodium salt of BCM; an optimum mixture contains 2% of the aluminum salt of NCH and 0.571 of the sodium salt of BCM, based on the total weight of the preservative.

A preserving agent for disperse dyes may contain up to 4% of the aluminum salt of NCH and up to 1% of BCM; an optimum mixture contains 2% of aluminum salt of NCH and 0.5% of BCM, based on the total weight of the disperse dye. This mixture is outstandingly suitable as an additive to disperse dyes for coatings in damp rooms to prevent fungal growth.

In addition te -their fungicidal effect. the pesticides according to the invention have anexcellent insecticidal action on ligniperdous insects such as Hylotrupes bajalus, Anobium punctatum and Lyctus brunncus. The following ligniperdous and wood-discoloring fungi as well as soft-rot and mold fungi may be controlled by the pesticides according to the invention: Merulius Iacrimans, Cmziop/mra (ere/2611a, Lentinus lepideux, Poria Vaporaria, Lcnzitc's rraheq, Paxillus panuoides; Pullularia mlluluns, Aspergillus niger, Bispora effusa, Staclzyhotrys atra, "Iriclmderma viride, Paecilomyces variutii, Claa'osporium herbarum, Scleroplmma piryophila, Chaetomium globosum, Hormiscium' spec, Stempliylium spec, Alternariu span, and Phoma violacea.

The pesticides according to the invention may not only be used as fungicidal and insecticidal constituents of oily wood perservatives; they are also suitable for the preservation of industrial products such as distempers, disperse dyes, leather, adhesives and paper, and also for the production of mold-resistant paints and oleoresin, alkyd resin and synthetic resin surface coatings.

The pesticides according to the invention maybe used by treating, for example impregnating or brushing, wood therewith, or by mixing them with liquids to be protected against pest attack, or by mixing with liquids which are to provide pesticidal properties.

The production of concentrates of active substances and further processing into oily wood preservatives are described in the following examples.

EXAMPLE 1 A 50% (by weight) active ingredient concentrate having a ratio of aluminum salt of NCH to sodium salt of BCM of 2:1 is prepared as follows: 146.5 parts (by weight) of dipropylene glycol is heated at to C;

while stirring, a mixture of 103.5 parts of the aluminum salt of NCH (96.7% purity) and 50 parts of the sodium salt of BCM is added in portions. After all the solid active ingredients have dissolved the solution is allowed to cool; a viscous paste is obtained.

To prepared an oil wood preservative containing 1.5% of the mixture (ratio 2:1) of the active ingredients, 30 parts of the above concentrate is heated at 100C with 286 parts of an alkyd resin having a medium oil content (20% solid resin) until a homogeneous solution has formed. It is allowed to cool; at 80C there is added 484 parts of a naphtha fraction containing aromatics, the whole'is filtered if necessary to remove impurities and then at ambient temperature 200 parts of a naphtha fraction containing aliphatics is added.

EXAMPLE 2 A 25% active ingredient concentrate having a ratio of aluminum salt of NCH to sodium salt of BCM of 4:] may be prepared as follows: 75 parts of dipropylene glycol is heated at to C and 7.5 parts of the sodium salt of BCM is slowly introduced. The whole is allowed to cool and 100 parts of an aromaticscontaining naphtha fraction which also contains 30% of the aluminum salt of NCH in dissolved form is added to the solution.

To prepare an oily wood preservative containg 2.5% of active ingredient mixture (ratio 4:1 122 parts ofthe above concentrate has 14.3 parts of an alkyd resin of medium oil content added to it while heating, and the mixture is stirred until a homogeneous solution has been formed. 48.5 parts of a naphtha fraction containing aromatics is then added followed after cooling by 25 parts of naphtha fraction containing aliphaties.

To prepare water-repellent impregnation paints water repellents may be added to the oily wood preservative mixtures. Examples of suitable substances are zinc stearate, aluminum stearate and waxes. Inorganic or organic pigments may also be incorporated into the mixtures to achieve color effects.

To protect wood against fungal attack an amount of from 50 to 200 ml of the oily wood preservative described in Examples 1 and 2 is usually applied per m of wood surface by brushing, spraying or dipping. The amount applied is dependent for example on whether planed or rough wood is to be protected and what protective effect is to be achieved. The amount of active ingredient mixture necessary to protect the wood is from 1 to 10 and preferably from 2 to 5 grams per in of wood surface; preferred amounts are 2.5 g (mixture ratio 4:1) and 3 g (mixture ratio 2:1 calculated as a mixture of the solid active ingredients without having regard to the amount of solvent, pigment and surface coating material.

The very good fungicidal and insecticidal effectiveness of the agents according to this invention will be seen from the following Examples.

EXAMPLE 3 In accordance with Butins method (Verschaerfte Muendener Streifenmethode; Verfahren zur Bewertung der blaeuehemmenden Eigenschaften oeliger Grundiermittel, described in the periodical Farbe und Lack, 71, No. 5, 1965, pages 373 to 374) the effectiveness of the active ingredient mixtures described in Example 1 and 2 are tested on the sap-staining fungi Sclerophoma pityophila and Pullularia pullulans. As comparative agents, mixtures are used which contain either 1% of the aluminum salt of NCll-I or 0.5% of the sodium salt of BCM. These mixtures are composed as follows:

a. 1% (by weight) of the aluminum salt of NCH, of an oil-modified alkyd resin, 30% of a naphtha fraction containing aliphaties and 59% of a naphtha fraction containing aromatics;

b. 0.5% of the sodium salt of BCM, 3% of dipropylene glycol, 14.5% of an oil-modified alkyd resin, 42% of a naphtha fraction containing aliphaties and 40% of a naphtha fraction containing aromatics. The control surfaces (without active ingredient) are painted with linseed oil varnish.

To carry out the tests, pine sapwood boards are treated on one half once with 50 or 100g or in two operations with 2 X 100 g of the wood preservative mixture. The control surfaces are coated with the same amount of linseed oil varnish. After a colorless alkyd resin coating material has been applied the boards are weathered for six months and then placed in Kolle culture flasks for fungus testing. After the test is over the control surfaces of the test boards have been discolored to an average extent of 90% by the growth of Sclerophoma pityophila and Pullularia pullulans. The results of the tests are given in the following Table. The efficiency of the mixtures of active ingredients and of the individual active ingredients is calculated by Abbots formula:

attack in control attack in test efficiency 74 In the Table the following mixtures or substances are used:

A according to Example 1 B according to Example 2 C aluminum salt of NCH D sodium salt of BCM E linseed oil varnish without active ingredient The columns in the Table are as follows:

1 amount in g/m applied to pinewood surface 2 amount in g/m of NCH and BCM applied to pinewood surface 3 percentage of wood surface discolored 4 efficiency in of active ingredient mixture 5 efficiency in of individual active ingredients 6 sum in of the actions of the individual active Pine sapwood blocks having the dimensions 50 mm X 25 mm X 15 mm are each coated with the wood preservative mixtures described in Examples 1 and 2 at the rate of 100 and 200 g/m of wood surface to determine their effectiveness against wood-destroying fungi in accordance with German Standard Specification DIN 52,176, page I: Pruefung von Holzschutzmitteln, Mykologische Kurzpruefun g (Kloetzchen- Verfahren)." After storage for 4 weeks-the treated blocks and untreated blocks are placed in culture flasks which contain as test fungi Coniophora cerebella and Merulius lacrimans. The flasks are then incubated in an air-conditioned room at a temperature of 22C and a relative humidity of After four months the blocks are taken out, freed from adhering fungus mycelium and dried. The extent of wood destruction is then determined by ascertaining the weight loss and by employing the DIN evaluation scheme. The results are shown in the following Table in'which the abbreviations have the following meanlngs:

A mixture according to Example 1 B mixture according to Example 2 F untreated control (a) amount of mixture applied in g/m of pinewood surface (b) percentage loss in weight using Coniop/wra cer ebella as test fungus (c) degree of destruction caused by Coniophora cerebella (a) (c) (d) (e) EXAMPLE 5 The prophylactic effectiveness of wood preservative mixtures against wood-destroying insects is tested in accordance with the German Standard Specification DIN 52,163 using the larvae of house longhorn beetles (Hylotrupes bajulus). Pine sapwood blocks having the dimensions 50 mm X 25 mm X mm are used. The rate of application is 50 and 100 g/m of wood surface. After the larvae have been placed on the small test blocks the latter are exposed at C and a relative humidity of 65% over a period of 4 weeks to the attack of the larvae. The test results are given in the following Table:

Condition of the larvae Wood preservative from after four weeks:

Example 2: application rate Active ingredient mixtures of the aluminum salt of NCH and BCM and the sodium salt of BCM in the ratios 2:1, 3:1 and 4:1 (based on the weight of active ingredient) are carefully incorporated in finely ground form into a plastics emulsion paint containing an acrylic ester copolymer as binder for the production of coating films resistant to attack by mold fungus. The amount of preservative added to the emulsion paint is from 1.5 to 4%. For comparison the individual active ingredients are added to the emulsion paint in the same way in amounts of from 0.5 to 3%. Pinewood boards (veneers) having dimensions of 50 mm X 50 mm X 1 mm are uniformly coated with the emulsion paint to determine the fungicidal resistance of the paint. After the Fungus spread on the Percentage of active paint surface after:

ingredient added to the emulsion paint: Al salt Na salt of NCH of BCM 2 weeks 4 weeks 6 weeks 1 0.5 O 0 1 1.5 0.5 0 0 1 2 1 0 O 0 3 1 0 0 0 1 O 1 3 1.5 0 3 2 0 1 2 3 0 0 l 0.5 l 3 3* l l 2 3* Al salt BC M of NCH 1 0.5 0 l l 1.5 0.5 0 0 l 2 l O 0 0 3 2 (l 0 O 1 0 1 3 1.5 0 l 3 2 0 l 2 v 3 0 0 1 0.5 l 2 3* 1 0 2 3* control (untreated) 2 4 5 mainly Alternaria and Trichoderma 0 surface free from fungal growth graduated down to 5 surface entirely covered hy fungus.

* mainly Alternaria and Trichoderma 0 surface free from fungal growth graduated down 5 surface entirely covered by fungus.

We claim:

1. A pesticide for the protection of wood comprising a mixture of (a) methyl 2-benzimidazolecarb amate or the sodium salt thereof and (b) the aluminum salt of N- nitrosoN-cyclohexylhydroxylamine, said mixture having a weight ratio of (b):(a) of from 2:1 to 4:1.

2. The pesticide of claim 1 which contains as solvent a compound selected from the group consisting of methyl glycol, n-butyl glycol, methyl diglycol, ethyl diglycol, dipropylene glycol, butyl diglycol, monoethylene glycol, diethylene glycol, tricthylene glycol and propylene glycol.

3. The pesticide of claim 1 which contains dipropylene glycol as a solvent.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 1 3,903,288 DATED September 2, 1975 |N\/4ENTOR(S) POMMER et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

n the Heading, insert [30] Foreign Application Priority Data October 13, 1972 Germany P 22 5O 28] .4 and August 18, 1973 G rmany P 23 41 882.8

In Column 6, Lines 42 through 45, delete the second occurence of footnotes.

Signed and Scaled this Fourteenth Day Of September 1976 [SEAL] A ttest:

RUTH C. MASON Arresting Officer C. MARSHALL DANN Commissioner uj'lalents and Trademarks 

1. A PRESTICIDE FOR THE PROTECTION OF WOOD COMPRISING MIXTURE OF (A) METHYL 2-BENZIMIDAOLECARBAMATE OR THE SODIUM SALT THEREOF AND (B) THE ALUMINUM SALT OF N-NITROSO-NCYCLOHEXYLYLDROXYLAMINE, SAID MIXTURE HAVING A WEIGHT RATIO OF (B) (A) OF FROM 2:1 TO 4:1
 2. The pesticide of claim 1 which contains as solvent a compound selected from the group consisting of methyl glycol, n-butyl glycol, methyl diglycol, ethyl diglycol, dipropylene glycol, butyl diglycol, monoethylene glycol, diethylene glycol, triethylene glycol and propylene glycol.
 3. The pesticide of claim 1 which contains dipropylene glycol as a solvent. 